git ssb

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var pull = require('pull-stream')
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var asyncMemo = require('asyncmemo')
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module.exports = function (sbot) {
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  return asyncMemo(getVotes, sbot)
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}
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function getVotes(sbot, id, cb) {
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  var upvoters, downvoters
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  var result = {
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    upvoters: upvoters = {},
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    downvoters: downvoters = {},
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    upvotes: 0,
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    downvotes: 0
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  }
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  var opts = {
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    dest: id,
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    rel: 'vote',
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    values: true,
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    keys: false
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  }
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  pull(
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    sbot.links(opts),
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    pull.drain(processMsg, function (err) {
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      if (err) return cb(err)
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      cb(null, result)
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      // keep the result updated
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      opts.live = true
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      opts.gte = Date.now()
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      pull(
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        sbot.links(opts),
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        pull.drain(processMsg, function (err) {
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          if (err) console.error('votes', err)
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        })
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      )
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    })
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  )
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  function processMsg(msg) {
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    if (!msg || !msg.value) return
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    if (msg.sync) return cb(null, result)
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    var vote = ((msg.value.content || 0).vote || 0).value
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    var author = msg.value.author
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    // remove old vote, if any
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    if (author in upvoters) {
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      result.upvotes--
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      delete result.upvoters[author]
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    } else if (author in downvoters) {
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      result.downvotes--
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      delete result.downvoters[author]
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    }
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    // add new vote
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    if (vote > 0) {
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      result.upvoters[author] = vote
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      result.upvotes++
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    } else if (vote < 0) {
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      result.downvoters[author] = vote
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      result.downvotes++
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    }
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  }
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}
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